1. Field of the Invention
The present invention relates to an ink jet recording apparatus. More particularly, the present invention relates to a method for checking a contact status of nozzles mounted on an ink jet recording head.
2. Description of the Related Art
An image recording apparatus can be a wire dot printer, a thermal printer, an ink jet printer etc. An image recording apparatus may include a unique recording head for recording image data on a recording medium such as a recording paper and an OHP (overhead project) film. Among the such mentioned various image recording apparatuses, the ink jet recording apparatus is an image recording apparatus that ejects ink on the recording medium for recording the image data. A recording head, employed in such an ink jet recording apparatus, may include a plurality of nozzles each having a fine ejection hole. Upon being heated by heating elements mounted on the respective nozzles, the ink filled in the nozzle is expanded and ejected from the nozzle. The ejected ink is transferred to the recording medium. Such an ink jet recording apparatus records the image data by selectively driving the nozzles mounted on the recording head according to the image data to be recorded. The nozzles are driven by a head driver circuit. When the ink jet recording apparatus records graphic or text data, a white horizontal line may occur on the recorded image. This is undesirable, as it degrades the quality of the recorded image. In some parlance, the occurrence of the white horizontal line is called a "nozzle slip-out phenomenon." The nozzle slip-out occurs not only when the nozzle is choked up, but also when the nozzle has a poor contact. Thus, the detection the nozzle slip-out and the detection of the cause of the nozzle slip-out are important. Among exemplars of this art of such types of control, sensing, and arrangement of the nozzles and printeads, Merkel et al. (U.S. Pat. No. 5,604,521, Self-Aligning Orifice Plate For Ink Jet Printheads, Feb. 18, 1997) discusses an orifice plate having a projection that is configured to be closely received by a corresponding alignment cavity in the front end body portion of the printhead. Hayes et al. (U.S. Pat. No. 5,581,286, Multi-channel Array Actuation System For An Ink Jet Printhead, Dec. 3, 1996) discusses ejecting volume modulatable droplets of ink from the ink jet printhead by sequentially applying a voltage pulse having a selected time duration to the first ink carrying channel and a voltage pulse having a time duration ranging between zero and the selected time duration to the second ink carrying channel. Tamura (U.S. Pat. No. 5,574,488, Liquid Jet Head, Liquid Jet Head Cartridge, And Liquid Jet Apparatus, Nov. 12, 1996) discusses a liquid jet head for recording, having elements for generating discharge energy to discharge a liquid. The head has a plurality of liquid passages and is pressed to be in close contact with the surface of the elemental base board on the side where the elements for generating discharge energy are arranged. Takagi (U.S. Pat. No. 5,389,961, Ink Jet Printer With Variable-Force Ink Declogging Apparatus, Feb. 14, 1995) discusses an ink jet printer having an apparatus for preventing ink clogs from interfering with the flow of ink from a printing nozzle during a printing operation. A printing nozzle is operably coupled to the chamber when the printing nozzle is not being used in a print operation. Allen (U.S. Pat. No. 4,542,389, Self-Cleaning Ink Jet Drop Generator Having Crosstalk Reduction Features, Sep. 17, 1985) discusses a nozzle plate having isolator holes which are connected to a refill plenum to help dissipate disturbance energy in the ink to reduce fluidic crosstalk between emitters in multi-emitter heads. Tamai (U.S. Pat. No. 4,357,614, Ink Particle Jetting Device For Multi-Nozzle Ink Jet Printer, Nov. 2, 1982) discusses a ink jetting device in which a plurality of silicon chips having nozzle arrays formed therein are mounted on a substrate having a plurality of holes therein with the nozzle arrays confronting the holes of the substrate. From my study of the contemporary practice and art, I find that there is a need for an improved and effective control, sensing, and arrangement of the nozzles and printheads, especially the particular control sequences of the present invention.